Meaning the baby, not the Chancellor!
If his father's only income was his RAF's officer income, with a salary under £50k, and with a non-earning mother, they would receive the full child benefit of £20.30 per week, or £1,055.60 per year until as late as 31 August 2033 if he is in qualifying education or in the armed forces by then.
If his father receives a pay rise in the next 16 to 20 years, taking his income over £50k, child benefit is reduced or if it reaches £60k, becomes £NIL. This assumes the thresholds aren't increased with wage inflation which is probably the intention.